Device for testing watch-balances and hair-springs



(No Model.)

A. L. KELLER.

DEVICE FOR TESTING WATCH BALANCES AND HAIR SPRINGS. No. 353,418.Patented Nov. 30; 1886.

N. PETERS. Phalo-Lilhognphur, Wahingtori. 0.1;

UNITED STATES PATENT OFFICE.

A. LINCOLN KELLER, OF SPRINGFIELD, MASSACHUSETTS.

DEVICE FOR TESTING WATCH-BALANCES AND HAIR-SPRINGS.

SPECIFICATION forming part of Letters Patent No. 353,418, dated November30, 1886.

Serial No. 210,608, (No model.)

To aZZ whom it may concern:

Be it known that I, A. LINCOLN KELLER, a citizen of-the United States,residing at Springfield, county of Hampden, and State of Massachusetts,have invented a new and useful Machine for Determining the Strength ofHair- Springs and Momentum of Balance-'Wheels of Watches, of which thefollowing is a specification.

The object of my invention is, more partied larl y in the manufacture ofwatches, to test the hairspring and balance-wheel to enable thedeviation of either from the true time, when either is combined with astandard balancewheel or hair-spring, to beindicated, so that a plus orminus degree of speed in the one may be compensatedfor by itscombination with the other having the exact opposite degree of deviationas, for instance, a hair-spring being vibrated with a balance-w heeladopted as a standard, and showing a retardation of five seconds, will,upon being combined with a balance-wheel which showed, upon being testedwith a standard spring, an acceleration of five seconds, form aregulator which will, when combined with the rest of the movement of awatch, form a true time-piece; and the inve1ition consists in thecombination and construe tion, as hereinafter described, and moreparticularly pointed out in the claims.

' My invention is fully illustrated in the accompanying drawings, inwhich Figure I is a plan view of my machine with the top portionremoved. Fig. II is a plan view of the top part. Fig. III is anelevation in section on the dotted line 00 x of Figs. I and II, andFigs. IV and V are detail views of parts of the mechanism.

D is the base, upon which is secured at an interval of space twowatch-movements, A B.

A is a standard already regulated to move without variation.

B is a movement-,a counterpart of the one A,

' except that the regulating hair-spring a and centrically to the axis01' the fourth wheel, so as to rotate with it.

W is a lever hinged between the two movements A B at w and adapted tovibrate in the plane of the base D, to have its free ends project withinthe movements A B and engage with the mechanism of each.

h is an arm attached to a rockshaft, i, and adapted to, upon the rockingof the shaft i by means of its handle I, vibrate thelever W, and m is aspring bearing continuously upon the lever W and operating to bear it inthe opposite direction from the intermittent movement of arm h. The endotlever \V entering movement A is provided with a detent, 0, adapted tofit into the notch d of cam 11, and the end of lever \V passing intomovement B is adapted to engage with one of the wheels thereof toinstantly stop the movement. In the drawings it is shown bearing uponthe periphery of the escape-wheel, as I have found in practice that theslightest pressure upon said wheel instantly stops the movement.

As shownin Fig. I, both movements A and B being wound, a swing of thehandle I in the direction indicated in dotted lines swingslever \V tosimultaneously permit both movements A B to startthe one A by thewithdrawal of detent o from the notch of cam d, and the one B by therelief of contact of the end of the lever from escape-wheel y. The cam(1 having started to rotate with the fourth wheel. H, the position ofnotch 01 has changed,so that the detent 0 rests upon the periphery ofthe rotating cam when the lever Wis released by handle I, and the otherend of the lever is held removed from escape-wl1eel 3 As notch (1 comesunder detent 0 spring m forces the detent therein and brings the otherend of the lever XV against the escape-wheel y to synchronously stopboth movements. As the fourth wheel, H, and consequently the cam d,makes a complete rotation in sixty seconds, it will be seen that anydeviation in the movement B from the standard A during that time wouldbe indicated by a hand moving with.

the spindle of the fourth wheel of movement B and stopping with it, andI arrange upon the spindle e of the fourth wheel of movement B a rod(not shown in elevation) to extend up above the top 0 of the device andcarry a hand, F, over a dial, G, secured to the top and in convenientview. The top rests upon and is secured to posts J from the base D, and,with sides connecting it with the base D, not only excludes all dustfrom the delicate mechanism thus inclosed, but serves as a rest for dialG andjournal bearings for the rock-shaft i and for rock-shaft s. Thehand-carrying rod from spindle e is sleeved to pass over said spindleend, to form a friction-joint therewith, and said rod is provided with aheart-cam, t, operating in connection with arm a of rock-shaft s, bymeans of whichas is common in stopwatches-the hand F is brought to thesame starting-point on the dial G. Both shafts i and s are preferablyprovided with stops and returning-springs, as shown in Figs. II and III.

Accessible for easy removal in the movement B is the hair-spring aandbalance-wheel b, and in factories where balance-wheels and hairspringsare to be combined to complete otherwise standard movements a balancewheel adopted as a standard is combined with an untested hair spring,and together placed, as shown in Fig. I, to make part of movement B. Thetwo mechanisms A B are then started, and the deviation of the two at theend of sixty seconds, and due to the hairspring, is, as indicated byhand F on dial G, recorded upon that spring, whether so many seconds orfractions of seconds, fast or slow. Any number of hair springs may be sotested and marked. The hair-springs being so marked or sorted, ahair-spring adopted as astandard is combined with an unknownbalance-wheel, and successively with any number of balance-wheels toobtain a record of their deviation individually.

To combine the two to complete a Watch- I showing the tenth or twentiethpart of a second, and by the deviceI obtain almost perfect accuracy inthe adjustment of the two parts of the vibrating mechanism of a watch toregulate the whole movement to astandard of comparison. In Fig. IV aportion of lever W is shown, with its detent resting upon the edge ofcam d and removed from notch d, and in Fig. V the opposite end of saidlever is shown removed from contact with escape-wheel y.

The construction of the mechanism of watches being so well known, it isnot deemed necessary to more fully illustrate the parts only generallyindicated in the-drawings.

Now, having described my invention, what I claim is- Thewithin-described mechanism for determining the strength of hair-springsand momentum of balance-wheels of watches, consisting of twowatch-movements, A B, fixed at an interval apart,- intermediatemechanism, sub stantially as shown.operatively connected with the fourthwheel of movenlentAand the mechanism of movement B, and adapted to startand automatically stop the two movements synchronously, and a hand uponthe prolonged spindle ofthe fourth wheel of movement B and adapted torotate with it, whereby a difference in the rate of speed of the fourthwheels of the two movements is indicated, as and for the purpose setforth.

- A. LIN GOLN KELLER.

Witnesses:

R. F. HYDE, PENN TYLER.

